CN114374276A

CN114374276A - Device comprising object and object movement detection means, input means and method of operation

Info

Publication number: CN114374276A
Application number: CN202111205345.7A
Authority: CN
Inventors: 爱德华·鲁夫
Original assignee: Chairui Europe Ltd
Current assignee: Cherry Europe Co ltd; Zhuhai Queli Electronics Co ltd
Priority date: 2020-10-15
Filing date: 2021-10-15
Publication date: 2022-04-19
Also published as: US20220123747A1; DE102020132196B4; CN114427960A; US11811399B2; DE102020132198A1; DE102020132196A1; US11817857B2; US20220123749A1; CN114427961A; US20220123750A1; DE102020132195A1; DE202020105904U1

Abstract

The application relates to a device comprising an object and an object motion detection means, an input means and a method of operation. The invention relates to an apparatus comprising a primary coil, an object movable relative to the primary coil, and means for detecting movement of the object relative to the primary coil. The apparatus comprises a resonant circuit and a secondary coil with coil turns that moves with or initiated by the object. The primary coil has turns and is part of a resonant circuit that also includes a capacitor. The secondary coil is shorted. The primary coil and the secondary coil are inductively coupled to each other during movement of the object between the first and second positions, and thus also during corresponding movement of the secondary coil. Here, the strength of the inductive coupling changes, and thus the physical quantity of the resonance circuit changes. The device comprises a measuring device for detecting and/or processing a physical quantity of the resonant circuit that changes when the object is moved between the first and second positions and outputting an electrical signal that depends on the change in the physical quantity.

Description

Device comprising object and object movement detection means, input means and method of operation

The invention relates to a device comprising a movable object (Objekt) and means for detecting the movement of the object. The invention also relates to an input device with one or more such devices

Such as a keyboard or a computer mouse, and to a method for operating such an apparatus or such an input device.

The motion of an object must be detected in a plurality of devices or apparatuses. One example is an input device such as a keyboard. For example, in a keyboard, but also in many other devices and apparatuses, it is necessary to detect actuation of a key and thus movement of a keycap as a movable object. Various types and configurations of key modules are known for effecting movement of the keycap. Through these key modules, the movement of the keycap is detected by a mechanical device that closes the electrical circuit. In other devices and apparatuses, the detection of the movement of the object is usually also achieved mechanically.

A disadvantage of these mechanical solutions is that material wear, in particular mechanical wear, for example on the electrical contact surfaces, is unavoidable. As a result, as the length of use increases, false switches or other malfunctions may occur more frequently, and even breakage of mechanical components may occur.

Another disadvantage of mechanical solutions is that only one determined switching point can be detected when the object is moving. This switching point is predefined in a fixed manner. However, in many applications it may be advantageous if this switching point can be changed, for example to advance or retard the trigger signal. Therefore, adjustability of the switching point is desirable.

Furthermore, the mechanical solution has the disadvantage that only one signal is triggered per actuation. Thus, variable signals that are graded at various levels or fine levels, or even stepless, depending on the motion or position of the object are not possible, but such variable signals are advantageous in many applications.

The invention is therefore based on the object of proposing a new device of the aforementioned type, in particular a device which makes it possible to achieve a longer service life than mechanical solutions and/or to extend the possibilities of detection and processing of object movements and thus at least partially overcomes the disadvantages described above. Furthermore, a new input device with such a device and a method for operating such a device should be proposed.

This object is achieved by a device having the features of claim 1 or claim 2, an input apparatus having the features of claim 15 and a method having the features of claim 16. Advantageous embodiments and developments are specified in the respective dependent claims.

The device according to the invention comprises a primary coil, an object movable relative to the primary coil, and means for detecting the movement of the object relative to the primary coil.

The means for detecting a movement of the object relative to the primary coil further comprise an electrical resonance circuit and at least one secondary coil with one or more coil turns, which moves with or initiated by (i.e. caused by) the object. The secondary coil may be arranged on or in the object. The secondary coil can be connected in a stationary manner to the object and thus move together with the object, so that the secondary coil performs the same movement as the object. It is also possible that the secondary coil is movably connected to the object directly or indirectly via other components, so that a movement of the object, although causing a movement of the secondary coil, does not necessarily correspond to a movement of the object. For example, the object may perform a linear motion, which causes a tilting motion in the secondary coil. This is the case, for example, when the secondary coil is movably connected to the object on the one hand and to another object which does not move with the object on the other hand.

The primary coil has one or more turns and is part of a resonant circuit that also includes at least one capacitor.

The secondary coil is shorted. In a coil with defined ends, this is to be understood as meaning that the two ends of the coil are electrically connected to one another in an at least virtually resistance-free manner. This results in a circuit which is at least substantially composed of only one or more turns of the secondary coil. In addition, a short-circuited secondary coil, which is understood to mean any closed form of an electrically conductive material, for example a ring or a frame, has a through-opening or a recess surrounded by the material, so that an electric current can flow around the opening or recess, for example a stamped part, in particular a ring-shaped or frame-shaped stamped part or a stamped part with a ring-shaped or frame-shaped area. In this case, the ends of the coils or turns cannot be defined, but rather the short-circuited coil in this case consists of a closed turn (geschlossene Windung), for example a loop or a frame. In the above case it is not excluded that the shorted coil has a switch via which the current flow through the shorted coil can be interrupted and also restored.

The primary coil and the secondary coil are inductively coupled to each other during a movement of the object between the first position and the second position and thus also during a corresponding movement of the secondary coil. During this movement, the strength of the inductive coupling between the primary coil and the secondary coil changes and, consequently, at least one physical quantity of the resonant circuit changes.

Furthermore, the device according to the invention for detecting a movement of an object relative to the primary coil comprises a measuring device for detecting and/or processing at least one physical quantity of the electrical resonance circuit which changes when the object moves between the first position and the second position. The measuring device also outputs at least one electrical signal that changes as a function of the physical variable, i.e., the measuring device has a corresponding device for signal output.

In particular, the device according to the invention has the advantage of contactless detection of the movement of the object and the resulting electrical signal output. The mechanical solution described in the opening paragraph and the problems associated therewith are abandoned. It is thus possible to produce devices and apparatuses which have a lower susceptibility to interference and a longer service life than the apparatuses of mechanical solutions. Furthermore, the contactless detection of the movement and the subsequently implemented signal output enable the detection process or the switching process to be kept constant in quality, for example, without the switching point or the switching reliability changing as a result of material wear or abrasion or breakage.

A further advantage of the invention is that the detection possibilities and processing possibilities for the movement of the object are extended. The inductive coupling changes continuously as the object moves. This applies correspondingly to the physical quantity detected by the measuring device, so that any switching point can be set variable and a variable signal can be output which reflects the movement or position of the object and, if appropriate, also the speed of this movement, for example in stages or in a finely graduated or stepless manner.

In particular, the inductive coupling of the primary coil and the secondary coil is performed in the manner of a transformer, wherein the secondary coil is additionally short-circuited.

Preferably, the resonant circuit is operated with an alternating voltage, in particular with an alternating voltage of a predetermined and/or adjustable frequency, and is connected to an appropriately equipped alternating voltage source for this purpose. The capacitor may be a variable capacitor with adjustable capacitance. Furthermore, the resonant circuit may additionally comprise at least one resistor, in particular a tunable resistor, in order to be used in particular for tuning.

Preferably, the frequency and/or the capacitor are adjusted or selected such that the resonant circuit is within the resonance range (also: within the resonance region) when the object is in a predetermined position relative to the circuit substrate. Usually, the alternating voltage powers a plurality of resonant circuits of a plurality of devices according to the invention, and therefore it is not possible to tune the frequency to a single resonant circuit. In this case, the adaptation of the resonant circuit with respect to its resonant range is achieved by adjusting the capacitance of the capacitors or selecting capacitors that are matched capacitively. By adjusting or selecting one or more resistors, the resonance strength or resonance bandwidth can be adjusted.

The resonant circuit is an LC tank circuit or, as a sub-case with a resistor, an LCR tank circuit.

The physical quantity may be a voltage, a current intensity, a resonance frequency, or an impedance of the primary coil. In particular, all measurable parameters of the resonant circuit or LC/LCR resonant circuit are understood to be this.

The inductive coupling between the primary and secondary coils may be performed without a metal core, such as an iron core, in the primary and secondary coils. This is advantageous for relatively high frequency operating voltages of the resonant circuit. However, it is also possible to provide a metal core in the primary coil and/or the secondary coil, which is particularly advantageous for relatively low-frequency operating voltages.

The device may have exactly one secondary coil. However, two or three or more secondary coils may be provided. For example, the secondary coils may differ in their respective inductive couplings with the primary coil, e.g., due to the different number of turns. The short-circuiting of the coils can be interrupted individually by providing respective switches, and thus only one or some of the secondary coils are inductively coupled to the primary coil in each case (except for the insignificant additional coupling of the secondary coils in the case of an open switch). Different movements can thus be detected and differentiated, for example, in a complex movement mechanism of the object in which the plurality of components of the secondary coil are formed.

The mode of action of the device according to the invention will be explained below:

the primary coil generates an alternating magnetic field around it, which penetrates the secondary coil. Thus, the primary coil and the secondary coil are inductively coupled via the alternating magnetic field. The alternating magnetic field emanating from the primary coil induces a voltage in the secondary coil. Since the secondary coil is shorted, a current flows in the secondary coil. This current flow is relatively strong compared to a non-shorted secondary coil due to the short-circuiting of the secondary coil and the low resistance associated therewith.

The current flow in the secondary coil in turn affects the primary coil and thus the resonant circuit (reverse coupling). This reverse coupling may cause a change in a physical quantity of the resonant circuit, such as the impedance of the primary coil, the resonant frequency, the voltage drop and/or the current flow. For example, if the secondary coil has a greater distance from the primary coil at a first location than at a second location, the inductive coupling is less at the first location than at the second location because the magnetic field strength and magnetic flux density decrease with increasing distance from the primary coil, and vice versa. Accordingly, in this example, the counter-coupling and thus the physical quantity change of the primary coil in the first position is also smaller than in the second position, and vice versa. This applies correspondingly to intermediate positions between the first position and the second position. For example, the physical quantity may also vary continuously or steadily between the first position and the second position, with continuous or steady movement between the positions.

The change in the resonant circuit causes an adjustment of the resonant circuit due to the change in the reverse coupling. For example, if the resonant circuit is operating at its resonant frequency with the secondary coil in a certain position relative to the primary coil, then the resonant frequency of the resonant circuit changes and the resonance decays when the position of the secondary coil changes. This causes a change in physical quantities, such as voltage and current, which can be detected by means of a measuring device and further processed. Based on this detection of the change of the one or more physical quantities, various hierarchical and stepless signal processing can be realized.

The same applies in reverse: if the resonant circuit is not operating at its resonant frequency, the change in the distance between the primary and secondary coils and the associated change in the inductive coupling and resulting adjustment of the resonant circuit may cause the resonant circuit to operate at a frequency close to or at the resonant frequency of the resonant circuit, with a corresponding effect on physical quantities such as voltage and current.

For example, differential control may also be implemented: in this case, the initial position is located between the first position and the second position, wherein the resonant circuit preferably runs in the assumed position in the region of the resonance side and is calibrated to a zero position of the detected physical quantity or physical quantities. Then, depending on the detected change in the one or more physical quantities in the signal output, the movement of the object in the first position direction may be evaluated as a negative movement of the object, whereas the movement of the object in the second position direction may be correspondingly evaluated as a positive movement of the object, or vice versa.

If the movable object has a movement mechanism and/or further components, it is advantageous if the parts of the movement mechanism and/or further components and/or the object itself do not have an electrically closed ring-like or frame-like element (which is made of a conductive material, for example metal, with an internal through-opening (durchgehende Ausnehmung) or opening) as long as they are not intended to form a secondary coil in the sense of the present invention. These elements may also inductively couple with the primary coil and interfere with the inductive coupling between the primary coil and the secondary coil. In order to avoid this, it is sufficient to electrically interrupt the ring or the frame at least at one point in the respective element. No current can then flow in these elements and there is therefore no or at least no relevant inductive coupling with the primary coil. This state corresponds to the transformer being in no-load operation.

An alternative apparatus according to the invention in turn comprises a primary coil, an object movable relative to the primary coil, and means for detecting movement of the object relative to the primary coil. The apparatus for detecting motion of an object in turn comprises an electrical resonance circuit and at least one secondary coil with one or more coil turns.

The primary coil in turn has one or more turns and is part of a resonant circuit which also includes at least one capacitor.

In this alternative solution, the secondary coil is also shorted. Here, reference is made to the above description relating to the above-mentioned solutions, which also apply to alternative solutions.

An alternative solution provides that the primary coil and the secondary coil are inductively coupled via a core, in particular an iron core or a ferrite core. In this case, the core and the secondary coil may be arranged on or in the movable object such that upon movement of the object a relative movement occurs between the core and the secondary coil on the one hand and the primary coil on the other hand, and such relative movement will change the strength of the inductive coupling between the primary coil and the secondary coil and thereby change the at least one physical quantity of the resonant circuit. Alternatively, the secondary coil is arranged positionally fixed relative to the primary coil, and only the core is arranged on or in the movable object, so that upon movement of the object a relative movement occurs between the core on the one hand and the secondary coil and the primary coil on the other hand, and this relative movement changes the strength of the inductive coupling between the primary coil and the secondary coil and thus changes at least one physical quantity of the resonant circuit.

In line with the above-described solution, it is also proposed in this alternative solution again that the means for detecting the movement of the object relative to the primary coil comprise measuring means for detecting and/or processing at least one physical quantity of the electrical resonance circuit which changes when the object moves between the first position and the second position and outputting at least one electrical signal which changes in dependence on this physical quantity, that is to say the measuring means have corresponding devices for signal output.

The above advantages and explanations of the above solutions apply analogously also to alternative solutions.

The invention provides an improvement to the two solutions mentioned above in that the shorted secondary coil is a planar coil. Alternatively or additionally, it can be provided that the shorted secondary winding has exactly one turn, wherein this turn is shorted.

According to an embodiment variant, the shorted secondary coil has exactly one turn, wherein the turn is shorted, and wherein the secondary coil is or comprises an element made of conductive material having a through-going notch (also: an opening) such that the conductive material enclosing this notch is the shorted turn of the secondary coil.

With regard to the shape of the secondary coil, it is only important that it has a through-opening, recess or opening surrounded by material, so that an electric current can flow around the recess or opening. For example, the secondary coil may be implemented in the shape of a ring or a frame.

According to an embodiment variant, the secondary coil is a short-circuited helical spring. For example, the helical spring may be a return spring, in particular a compression spring, preferably having a diameter corresponding to the diameter of the primary coil. In order to achieve a short circuit, the two ends of the helical spring can be electrically connected to one another, wherein the resistance of the connection is expediently small.

According to a further embodiment variant, the secondary coil is a stamped and/or bent part made of sheet metal.

In a development of the invention, the secondary winding has a switch for interrupting the short circuit. The switch can realize a hybrid circuit: in an initial position of the movable object and thus of the secondary coil, for example in the first position or in the second position, the switch is open and thus the short-circuiting of the secondary coil is interrupted. When the object and thus the secondary coil move out of the initial position, no back coupling, or at least no significant back coupling, of the primary coil and the resonant circuit, no change in physical quantities such as voltage and current of the resonant circuit, or at least no significant change, occurs, as a result of the short break and thus no current flow in the secondary coil, so that no movement of the object can be detected. If the switch is closed when the switching position is reached or exceeded and the coil is therefore shorted, this will result in a current flow in the secondary coil, together with a corresponding back coupling to the primary coil and thus to the physical quantity of the resonant circuit. Thus, further movements of the object and of the arrival at the switching position are detected and can be further processed in respect of the output of the at least one electrical signal.

In one embodiment of the invention, the device comprises a circuit substrate, to which the primary coil is fixedly connected. A circuit substrate is to be understood as, for example, a printed circuit board and/or a circuit foil (Folie) and/or a stamping and/or other substrate, in particular with an applied and/or integrated conductor circuit (Leiterbahn). The circuit substrate may also be composed of two or more layers, for example, two or more of the above-described layers. Furthermore, a circuit substrate is also to be understood as a reference component of any other reference device or apparatus, relative to which the object moves.

A development of the invention provides that the primary coil is a planar coil and/or is arranged on and/or in the circuit substrate and/or is arranged on the top side and/or on the bottom side of the circuit substrate and/or is arranged between at least two layers within the multilayer circuit substrate.

The primary coil may also be a cylindrical coil instead of a planar coil. Furthermore, the primary coil can also be arranged in or on a further component (for example a housing), which is connected to the circuit substrate in a positionally fixed manner.

The invention provides that one or more turns of the secondary winding lie in a plane parallel to the planar extent of the circuit substrate. This is advantageous, for example, in the case of the primary coil being configured as a planar coil located on or in the circuit substrate.

According to one embodiment of the invention, the primary coil has a primary coil axis and the secondary coil has a secondary coil axis, wherein the primary coil axis and the secondary coil axis are inclined at a maximum of 90 °, preferably at a maximum of 45 °, in particular at a maximum of 30 °, or extend parallel to one another, preferably lie on a common straight line.

The primary and secondary coils may be, but need not be, oriented in parallel. Likewise, the primary and secondary coils may also be inclined to each other. For example, various annularly closed components of the movement mechanism of the object, which are arranged parallel or obliquely with respect to the primary coil, composed of conductive material can form the secondary coil. The secondary coil may be one-piece or multi-piece, and the various parts of the secondary coil may also be moved relative to each other if necessary.

The measuring device may be configured such that at least one electrical signal is output when at least one limit value of change of the physical quantity is reached or exceeded. Alternatively or additionally, the measuring device may also be configured such that the signal strength of the at least one electrical signal changes in dependence on a change in the physical quantity.

It is also possible to specify two or more different change limit values in advance, for example using a first change limit value which acts in a first movement of the object and a second change limit value which acts in a second, for example reversed, movement of the object.

The mentioned change limit values can be specified in advance in a fixed manner. However, it is also possible for one or more of the change limit values to be adjustable. This has the advantage that the so-called switching point (i.e. the exact position of the object during the respective movement, at which the electrical signal is output) can be changed and thus adjusted without mechanical changes.

The measuring device may be configured such that the signal strength of the at least one electrical signal is related to the position of the object relative to the primary coil and/or to the distance between the primary coil and the secondary coil. For example, the variable signal may be output in stages or fine steps or even stepless. This is possible, for example, if: the movement of the secondary coil or the object enables a continuous, in particular continuous and/or stepless, change of the physical quantity detected during the movement. The measuring device can then be configured such that in the secondary coil or object movement the electrical signal is output in stepless or fine steps or stages, preferably with a corresponding change in signal strength also in stepless or fine steps or stages. In this way, for example, in a keyboard or a computer mouse, a so-called joystick function can be implemented which opens up new, widespread application possibilities, in particular in the field of games, but also in office applications and other applications, for example in the case of speed-variable scrolling of displayed documents, tables and websites or in the case of speed-variable control of objects.

Embodiments of the invention provide that the movable object can be moved perpendicular to the primary coil and/or linearly with respect to the primary coil. However, the movement of the object and thus of the secondary coil does not have to be perpendicular to the primary coil or realized in a linear movement. For example, a rotational movement and/or a tilting movement or any three-dimensional movement may also be realized.

The input device according to the invention comprises one or more devices according to the invention. The input device may be a keyboard or a computer mouse, for example. Each of the devices according to the invention is then associated with a keyboard or a key of a computer mouse, wherein the circuit substrate, if present, is usually associated with a plurality or all of the devices. In this case, the movable object is, for example, a key cap, which is, for example, movably mounted on the circuit substrate as a component of the key module.

The method according to the invention relates to a method of operation for an apparatus according to the invention and/or an input device according to the invention. By means of which the movement of the object relative to the primary coil is detected. The method comprises the following steps:

a) performing a movement of the object relative to the primary coil such that the inductive coupling between the primary coil and the secondary coil changes and thus also at least one physical quantity of the resonant circuit changes;

b) detecting and/or processing by means of a measuring device at least one physical quantity of the resonant circuit that changes as a result of the movement;

c) when a limit value of the change of the physical quantity is reached or exceeded, at least one electrical signal is output and/or the signal strength of the at least one electrical signal is changed in accordance with the change of the physical quantity.

The advantages of the method and further method steps result from the above description of the device according to the invention.

According to one embodiment, the resonant circuit is operated with an alternating voltage of a predetermined and/or adjustable frequency. Here, the resonant circuit is adjusted by adjusting or selecting the frequency and/or by adjusting or selecting the capacitance of the capacitor and/or by adjusting or selecting a resistor arranged in the resonant circuit such that the resonant circuit is in the resonance range when the object is in a predetermined position with respect to the primary coil.

Drawings

Further features and advantages of the invention will be explained in more detail below by means of a description of embodiments and with reference to the accompanying schematic drawings.

In the drawings:

figure 1 shows an embodiment of the device according to the invention in an exploded view,

fig. 2 shows a diagram illustrating the basic functional principle of the present invention, and

fig. 3 shows an exemplary illustration of an arrangement for detecting a movement of an object according to an embodiment of the device of the invention in the form of a circuit diagram.

Parts and components that correspond to each other are provided with the same reference numerals throughout the figures.

Fig. 1 shows an embodiment of a device 1 according to the invention in an exploded view. The device 1 is illustratively used for a keyboard or, more specifically, in conjunction with the keys of a keyboard. The device 1 comprises a circuit substrate 2, here a printed circuit board, and an object 3, here a key cap 3, which is movable relative to the circuit substrate 2. The key cap 3 is movably mounted on the circuit substrate 2 by means of a movement mechanism 15 (in fig. 1 for example a double wing mechanism comprising a base 16, two wing-like elements 17 and a spring 18 connecting the two wing-like elements 17) and can be moved perpendicular to the circuit substrate 2 in a manner known per se. Any other movement mechanism 15 may also be provided, such as a scissor-type mechanism.

Furthermore, in fig. 1, the device 1 also comprises a primary coil L1, which primary coil L1 is here a planar coil having a plurality of turns and is arranged on the top side of the circuit substrate 2, more precisely in the area of the base 16 in which the movement mechanism 15 is also arranged. In the assembled state, the base 16 almost encloses the primary coil L1, which is implemented as a planar coil, to some extent.

In fig. 1, the apparatus 1 further includes a secondary coil L2, which secondary coil L2 is configured as a stamped piece and is closed in a frame-shaped or ring-shaped manner. The secondary coil L2 is composed of a metal that encloses the notch 13 in a frame-shaped or annular manner. Thus, the secondary coil L2 is shorted and the induced current can flow around the notch 13. The secondary coil L2 is mounted on the bottom side of the movable object 3 (here the key cap 3) facing the circuit substrate 2 and moves together with this object 3. The secondary coil L2 shown in fig. 2 has exactly one coil turn.

In fig. 1, the primary coil L1 and the secondary coil L2 are inductively coupled to each other. This inductive coupling is also schematically illustrated in fig. 2. The primary coil L1 (in fig. 2 also a planar coil with a plurality of turns on the top side of the circuit substrate 2) is a component of the resonant circuit 11, which is explained below on the basis of fig. 3 and operates with an alternating voltage U1. Thus, the turns of the primary coil L1 are surrounded by the magnetic field 19 shown in fig. 2. In this magnetic field 19 there is a secondary coil L2 with a through-opening 13, which in fig. 2 is also a ring-or frame-like closing stamp, i.e. the secondary coil L2 is short-circuited and has only one turn. Due to the alternating voltage U1, the magnetic field 19 is an alternating magnetic field which, due to inductive coupling, induces a voltage in the secondary coil L2 and thus a current flow due to a short circuit, which in turn generates a counter-coupling with the primary coil L1. If the secondary coil L2 is now moved relative to the primary coil L1 (this is indicated in fig. 2 by the middle double arrow), this affects the strength of the inductive coupling and the physical quantities of the resonant circuit 11 to which the primary coil L1 belongs (e.g. voltage and current strength and resonant frequency) may change. The measuring device (not shown in the drawings) detects and processes at least one physical quantity of the electric resonance circuit 11 that changes upon movement of the secondary coil L2 due to movement of the subject 3, and outputs at least one electric signal that correlates with the change in the physical quantity.

Therefore, the device 1 comprises means 10 (not shown in fig. 1 and 2), which means 10 are used for detecting a movement of the object 3 relative to the circuit substrate 2 or the primary coil L1. The device 10 is shown as a circuit diagram in fig. 3. The arrangement 10 comprises the already mentioned electrical resonance circuit 11 with the capacitor C1 and the primary coil L1, wherein a resistor (not shown) may additionally be provided. The resonant circuit 11 operates at an alternating voltage U1. In this resonant circuit 11, only the primary coil L1 is shown in fig. 1.

As further shown in fig. 3, the device 10 further includes a secondary coil L2, the ends of which are electrically shorted via a shorting line 12. A switch 14 is provided in the short-circuit line 12, by means of which switch the short-circuit line 12 can be interrupted and closed again. The inductive coupling of the primary coil L1 and the secondary coil L2 is symbolically represented in fig. 3 by a double arrow between the two coils L1, L2. The alternating magnetic field generated by the alternating voltage U1 induces an alternating voltage U2 in the secondary coil L2, which alternating voltage U2, when the switch 14 is closed, causes a current flow in the secondary coil L2 due to the short circuit, which current flow causes a reverse coupling to the primary coil L1 and thus to the resonant circuit 11, thereby (as described above) causing a change in the physical quantity of the resonant circuit, which change is in turn detected via the measuring device, which has likewise been described, and causes a corresponding signal output.

List of reference numerals

1 apparatus

2 Circuit substrates, e.g. printed circuit boards

3 Movable objects, e.g. keycaps

10 device for detecting the movement of an object 3

11 resonant circuit

12 secondary coil L2 shorting circuit

13 notches in secondary coil L2

14 switch

15 kinematic mechanisms, e.g. double wing mechanisms

16 base

17 wing-shaped element

18 spring

19 magnetic field

C1 capacitor

L1 primary coil

L2 secondary coil

U1 AC voltage

U2 induces an ac voltage in the secondary coil L2.

Claims

1. An apparatus (1) comprising a primary coil (L1), an object (3) being movable relative to the primary coil (L1) and means (10) for detecting a movement of the object (3) relative to the primary coil (L1),

wherein the apparatus (10) comprises an electrical resonance circuit (11) and at least one secondary coil (L2) with one or more coil turns, the secondary coil (L2) moving with or initiated by the object (3),

wherein the primary coil (L1) has one or more turns and is part of the resonant circuit (11), the resonant circuit (11) further comprising at least one capacitor (C1),

wherein the secondary coil (L2) is shorted (12),

wherein the primary coil (L1) and the secondary coil (L2) are mutually inductively coupled during a movement of the object (3) between a first position and a second position and thus also during a corresponding movement of the secondary coil (L2), and in which movement the strength of the inductive coupling between the primary coil (L1) and the secondary coil (L2) changes and thus at least one physical quantity of the resonant circuit (11) changes,

wherein the means (10) for detecting the movement of the object (3) relative to the primary coil (L1) comprise measuring means for detecting and/or processing at least one physical quantity of the electrical resonance circuit (11) which changes when the object (3) moves between a first position and a second position, and outputting at least one electrical signal which changes in dependence on the physical quantity.

2. An apparatus (1) comprising a primary coil (L1), an object (3) being movable relative to the primary coil (L1) and means (10) for detecting a movement of the object (3) relative to the primary coil (L1),

wherein the device (10) comprises an electric resonance circuit (11) and at least one secondary coil (L2) with one or more coil turns,

wherein the primary coil (L1) has one or more turns and is part of the resonant circuit (11), which further comprises at least one capacitor (C1),

wherein the secondary coil (L2) is shorted (12),

wherein the primary coil (L1) and the secondary coil (L2) are inductively coupled via a core,

wherein the core and the secondary coil (L2) are arranged on or in a movable object (3), or the secondary coil (L2) is arranged positionally fixed relative to the primary coil (L1) and only the core is arranged on or in the movable object (3), such that upon movement of the object (3) a relative movement takes place between the core and the secondary coil (L2) on the one hand and the primary coil (L1) on the other hand, or between the core and the secondary coil (L2) on the one hand and the primary coil (L1) on the other hand, and said relative movement changes the strength of the inductive coupling between the primary coil (L1) and the secondary coil (L2) and thereby changes at least one physical quantity of the resonant circuit (11),

wherein the means (10) for detecting the movement of the object (3) relative to the primary coil (L1) comprise measuring means for detecting and/or processing at least one physical quantity of the electrical resonance circuit (11) that changes when the object (3) moves between a first position and a second position, and outputting at least one electrical signal that changes in dependence on the physical quantity.

3. Device (1) according to claim 1 or 2, characterized in that the shorted secondary coil (L2) is a planar coil and/or has exactly one turn, wherein the turn is shorted.

4. Device (1) according to any one of the preceding claims, characterized in that the shorted secondary coil (L2) has exactly one turn, wherein the turn is shorted, wherein the secondary coil is or comprises an element made of conductive material having a through notch (13) such that the conductive material enclosing the notch (13) is a closed turn of the secondary coil (L2).

5. Device (1) according to any one of the preceding claims, characterized in that the secondary coil (L2) is a shorted helical spring or a stamped and/or bent piece made of sheet metal.

6. Device (1) according to any one of the preceding claims, characterized in that the secondary coil (L2) has a switch (14) for interrupting the short (12).

7. Device (1) according to any one of the preceding claims, characterized in that the device (1) comprises a circuit substrate (2), the primary coil (L1) being fixedly connected with the circuit substrate (2).

8. Device (1) according to claim 7, characterized in that the primary coil (L1) is a planar coil and/or is arranged on and/or in the circuit substrate (2) and/or is arranged on the top side and/or the bottom side of the circuit substrate (2) and/or is arranged between at least two layers within a multilayer circuit substrate (2).

9. Device (1) according to claim 7 or 8, characterized in that one or more turns of the secondary coil (L2) are located in a plane parallel to the planar extension of the circuit substrate (2).

10. Device (1) according to one of the preceding claims, characterized in that the primary coil (L1) has a primary coil axis and the secondary coil (L2) has a secondary coil axis, wherein the primary coil axis and the secondary coil axis are at most inclined by 90 ° to each other or extend parallel to each other.

11. Device (1) according to any one of the preceding claims, characterized in that the measuring means are configured such that the at least one electrical signal is output when at least one limit value of the change of the physical quantity is reached or exceeded and/or that the signal strength of the at least one electrical signal is changed in accordance with the change of the physical quantity.

12. The apparatus (1) according to claim 11, characterized in that the change limit value or values are adjustable.

13. An apparatus (1) according to claim 11 or 12, characterized in that the measuring device is configured to make the signal strength of the at least one electrical signal dependent on the position of the object (3) relative to the primary coil (L1) and/or the distance between primary coil (L1) and secondary coil (L2).

14. The device (1) according to any of the preceding claims, characterized in that the movable object (3) is movable perpendicular to the primary coil (L1) and/or linearly with respect to the primary coil (L1).

15. An input device comprising one or more devices (1) according to any one of the preceding claims.

16. A method for operating a device (1) according to any one of claims 1 to 14 and/or an input apparatus according to claim 15, by which method a movement of the object (3) relative to the primary coil (L1) is detected, and which method comprises the steps of:

a) performing a movement of the object (3) relative to the primary coil (L1) such that the inductive coupling between the primary coil (L1) and the secondary coil (L2) changes and thereby also at least one physical quantity of the resonant circuit (11) changes,

b) detecting and/or processing by means of the measuring device at least one physical quantity of the resonance circuit (11) that changes as a result of the movement,

c) outputting at least one electrical signal when a limit value of the change of the physical quantity is reached or exceeded and/or changing the signal strength of the at least one electrical signal in dependence on the change of the physical quantity.

17. Method according to claim 16, characterized in that the resonance circuit (11) is operated with an alternating voltage (U1) of a predetermined and/or adjustable frequency and is adjusted there by adjusting or selecting the frequency and/or by adjusting or selecting the capacitance of the capacitor (C1) and/or by adjusting or selecting a resistor arranged in the resonance circuit (11) such that the resonance circuit (11) is in a resonance range when the object (3) is in a predetermined position with respect to the primary coil (L1).